001 /*
002 $Id: Expando.java,v 1.10 2005/10/03 18:07:36 tug Exp $
003
004 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005
006 Redistribution and use of this software and associated documentation
007 ("Software"), with or without modification, are permitted provided
008 that the following conditions are met:
009
010 1. Redistributions of source code must retain copyright
011 statements and notices. Redistributions must also contain a
012 copy of this document.
013
014 2. Redistributions in binary form must reproduce the
015 above copyright notice, this list of conditions and the
016 following disclaimer in the documentation and/or other
017 materials provided with the distribution.
018
019 3. The name "groovy" must not be used to endorse or promote
020 products derived from this Software without prior written
021 permission of The Codehaus. For written permission,
022 please contact info@codehaus.org.
023
024 4. Products derived from this Software may not be called "groovy"
025 nor may "groovy" appear in their names without prior written
026 permission of The Codehaus. "groovy" is a registered
027 trademark of The Codehaus.
028
029 5. Due credit should be given to The Codehaus -
030 http://groovy.codehaus.org/
031
032 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
036 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043 OF THE POSSIBILITY OF SUCH DAMAGE.
044
045 */
046 package groovy.util;
047
048 import groovy.lang.Closure;
049 import groovy.lang.GroovyObjectSupport;
050 import groovy.lang.GroovyRuntimeException;
051 import groovy.lang.MetaExpandoProperty;
052
053 import java.util.HashMap;
054 import java.util.Map;
055 import java.util.Map.Entry;
056 import java.util.List;
057 import java.util.ArrayList;
058 import java.util.Iterator;
059
060
061 /**
062 * Represents a dynamically expandable bean.
063 *
064 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
065 * @author Hein Meling
066 * @author Pilho Kim
067 * @version $Revision: 1.10 $
068 */
069 public class Expando extends GroovyObjectSupport {
070
071 private Map expandoProperties;
072
073 public Expando() {
074 }
075
076 public Expando(Map expandoProperties) {
077 this.expandoProperties = expandoProperties;
078 }
079
080 /**
081 * @return the dynamically expanded properties
082 */
083 public Map getProperties() {
084 if (expandoProperties == null) {
085 expandoProperties = createMap();
086 }
087 return expandoProperties;
088 }
089
090 public List getMetaPropertyValues() {
091 // run through all our current properties and create MetaProperty objects
092 List ret = new ArrayList();
093 Iterator itr = getProperties().entrySet().iterator();
094 while(itr.hasNext()) {
095 Entry entry = (Entry) itr.next();
096 ret.add(new MetaExpandoProperty(entry));
097 }
098
099 return ret;
100 }
101
102 public Object getProperty(String property) {
103 try {
104 return super.getProperty(property);
105 }
106 catch (GroovyRuntimeException e) {
107 return getProperties().get(property);
108 }
109 }
110
111 public void setProperty(String property, Object newValue) {
112 try {
113 super.setProperty(property, newValue);
114 }
115 catch (GroovyRuntimeException e) {
116 getProperties().put(property, newValue);
117 }
118 }
119
120 public Object invokeMethod(String name, Object args) {
121 try {
122 return super.invokeMethod(name, args);
123 }
124 catch (GroovyRuntimeException e) {
125 // br should get a "native" property match first. getProperty includes such fall-back logic
126 Object value = this.getProperty(name);
127 if (value instanceof Closure) {
128 Closure closure = (Closure) value;
129 closure.setDelegate(this);
130 return closure.call((Object[]) args);
131 }
132 else {
133 throw e;
134 }
135 }
136
137 }
138
139 /**
140 * This allows toString to be overridden by a closure <i>field</i> method attached
141 * to the expando object.
142 *
143 * @see java.lang.Object#toString()
144 */
145 public String toString() {
146 Object method = getProperties().get("toString");
147 if (method != null && method instanceof Closure) {
148 // invoke overridden toString closure method
149 Closure closure = (Closure) method;
150 closure.setDelegate(this);
151 return closure.call().toString();
152 } else {
153 return expandoProperties.toString();
154 }
155 }
156
157 /**
158 * This allows equals to be overridden by a closure <i>field</i> method attached
159 * to the expando object.
160 *
161 * @see java.lang.Object#equals(java.lang.Object)
162 */
163 public boolean equals(Object obj) {
164 Object method = getProperties().get("equals");
165 if (method != null && method instanceof Closure) {
166 // invoke overridden equals closure method
167 Closure closure = (Closure) method;
168 closure.setDelegate(this);
169 Boolean ret = (Boolean) closure.call(obj);
170 return ret.booleanValue();
171 } else {
172 return super.equals(obj);
173 }
174 }
175
176 /**
177 * This allows hashCode to be overridden by a closure <i>field</i> method attached
178 * to the expando object.
179 *
180 * @see java.lang.Object#hashCode()
181 */
182 public int hashCode() {
183 Object method = getProperties().get("hashCode");
184 if (method != null && method instanceof Closure) {
185 // invoke overridden hashCode closure method
186 Closure closure = (Closure) method;
187 closure.setDelegate(this);
188 Integer ret = (Integer) closure.call();
189 return ret.intValue();
190 } else {
191 return super.hashCode();
192 }
193 }
194
195 /**
196 * Factory method to create a new Map used to store the expando properties map
197 * @return a newly created Map implementation
198 */
199 protected Map createMap() {
200 return new HashMap();
201 }
202
203 }